You see those fin-like bones that rise up from the skull? All of that is filled with the muscle that closes the jaw - technically the purpose of these bones is for the muscle to attach to. One bite will slice and crush anything of you that is in his mouth.
Oh, and humans lack a type of fast-twitch muscle fibre that gorillas (and pretty much all non-human mammals) have. This makes their muscles a lot more powerful than ours, no matter what training you do. They will tire faster, but thats probably only during the stomp-on-your-bloody-remains part of the fight.
Oh, and their reaction speed is also faster.
Basically, you have zero chance going mano a mano with a gorilla.
Linux was not muscled like that in 1991 - it's first, barebones kernel was released in September of that year.
I remember installing Linux on a 90MHz 486 in the mid 90s and it barely ran X server with a simple window manager. And if the machine was turned off while Linux was running, you might not be able to boot again.
Linux now, however, is unrecognizeably better.